1. Field of the Invention
The application relates to a battery, and particularly to a lithium battery.
2. Description of Related Art
Since one-time used battery does not full fill the requirement of the environmental protection, the battery system capable of being recharged is getting a lot of interests. With the rapid development and popularization of the portable electronic products, the lithium batteries which can repeat the cycle of discharging-and-recharging have the advantages of light weight, high voltage and high energy density so that the market demands on the lithium batteries increase. Comparing with the nickel-metal-hydride battery, the nickel-zinc battery and the nickel-cadmium battery, the lithium battery has the advantages of high working voltage, large energy density, light weight, long lifetime and good environmental protection and the lithium battery is one of the best batteries for being applied in the flexible battery in the future.
The lithium batteries are widely used in the so-called 3C products including computers (i.e. the information products), the communication products and the consumer electronics so that the demands on the performance of the lithium batteries, such as light weight, durability, high voltage, high energy density and safety, become high. Further, the developmental potential and the application of the lithium batteries in the light-weighted electromobile industry, electric motor car industry and large-sized electronic storage industry are high. However, the organic solvents (most of these organic solvents include the organic molecules having ester groups) with high-voltage endurance which is used in the lithium battery system is flammable. Also, the positive electrode/negative electrode activity substance with high capacitance would decompose to generate a great amount of heat while the temperature of the battery increases so that the heat generated while the lithium battery is not properly used can ignite the organic solvent and even lead to the explosion. Moreover, during the discharge process of the lithium battery, since the oxygen is expelled from the positive electrode material structure, the expelled oxygen reacts with the electrolyte, which leads to the increasing of the internal temperature and induces safety problem of the lithium battery.